The colleague, who asked not to be named, said: "We knew he was a good climber but never thought he would scale the building that fast.

"He left us and the guy he was racing against totally gobsmacked.

"It wasn’t part of a standard training exercise but a bet between the two men who took part.

"I’m not sure what the loser had to do because they’re on a different shift."

The 'Spiderman Fireman' eventually scaled nine floors in his unconventional style

He added: "What I do know is that I’m 45 years old, the same age as Ale, and I couldn’t do what he does.

"Fitness is an important part of our job but most other fireman wouldn’t be capable of what he did either.

"The video was shot around 12 days ago and at first we got a lot of criticism because people thought he was climbing without safety ropes and hadn’t seen the harness. The reality is that what we did was totally safe.

“A few years ago Ale went on a TV programme where the contestants had to take part in testing challenges.

“In one he scaled a wall blindfold and made it look so easy that the programme makers had to tell him to slow down and pretend it was more difficult for him than it was.

Don't look down: Alejandro beats his competitor to the top floor

He added: “He’s not into Crossfit or a regular top-level sports participant and he’s not a big muscleman, far the opposite because there’s nothing to him.

“He just keeps himself in shape and has got an extraordinary ability when it comes to climbing.”

Spaniard Llanos Rodriguez Romero wrote on social media: “These sort of people don’t normally appear in the media or get paid huge salaries like politicians.

“But they risk their lives every time they go out to help a person who is in difficulty.”

Pedro Monserrat added: “Long live the mother who gave birth to this man. You’re a real super hero. Congratulations to firemen around the world.”

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